package com.example.gulimall.cart.interceptor;

import com.example.common.constant.AuthServerConstant;
import com.example.common.constant.CartConstant;
import com.example.common.vo.MemberRespVo;
import com.example.gulimall.cart.to.UserInfoTo;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.UUID;

/**
 * 在执行目标方法之前，判断用户的登录状态，并封装传递给controller目标请求
 */
@Component
public class CartInterceptor implements HandlerInterceptor {
    public static  ThreadLocal<UserInfoTo> threadLocal=new InheritableThreadLocal<>();
    @Override
  public  boolean preHandle(HttpServletRequest request,
                            HttpServletResponse response, Object handler) throws Exception {
        UserInfoTo userInfoTo = new UserInfoTo();
        HttpSession session = request.getSession();
        MemberRespVo member = (MemberRespVo)session.getAttribute(AuthServerConstant.LOGIN_USER);
        if (member!=null) {
            //用户登录了
            userInfoTo.setUserId(member.getId());
        }
        // 获取cookie 如果已经有key了则赋值给userInfoTo
            Cookie[] cookies = request.getCookies();
            if (cookies!=null&&cookies.length>0){
                for (Cookie cookie : cookies) {
                    String name = cookie.getName();
                    if (name.equals(CartConstant.TEMP_USER_COOKIE_NAME)){
                        userInfoTo.setUserKey(cookie.getValue());
                        //标记为已是临时用户,后面postHandle方法中不用再发cookie
                        userInfoTo.setTempUser(true);
                    }
                }
            }

        //如果没有临时用户分配一个用户还没有user-key发一个
        if (StringUtils.isEmpty(userInfoTo.getUserKey())){
            String s = UUID.randomUUID().toString();
            userInfoTo.setUserKey(s);
            //让postHandle给他发一个cookie
        }
        //目标方法执行之前,将封装好的数据放到threadLocal,同一个线程共享数据
        threadLocal.set(userInfoTo);
        return  true;
    }

    /**
     * 业务执行之后
     * @param request
     * @param response
     * @param handler
     * @param modelAndView
     * @throws Exception
     */
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

        UserInfoTo userInfoTo = threadLocal.get();
        if (!userInfoTo.isTempUser()){
            //没有临时用户才放cookie发放一个临时用户
            Cookie cookie = new Cookie(CartConstant.TEMP_USER_COOKIE_NAME,userInfoTo.getUserKey());
            cookie.setDomain("mall.com");
            cookie.setMaxAge(CartConstant.TEMP_USER_COOKIE_TIMEOUT);
            response.addCookie(cookie);
        }
        //CartInterceptor.threadLocal.remove();//清空threadLocal


    }
}
